Engine Code P1594

[Swashbuckle]

Hi everyone,

this is my first post, however I have been lurking for quite a while. I got this code a couple of weeks ago (P1594 Charging System Voltage Too High Battery voltage sense input above target charging voltage during engine operation) and have yet to find a solution to it. The battery is seemingly getting way overchaged enough that it is leaking through the top caps, however I didn't see any overhcarge when I tested with a voltmeter.


I have had the battery and alternator tested and both were fine, my next guess is going to be the battery temperature sensor and lastly the PCM.


Has anyone had any kind of experience like this?
Its driving me crazy.

The truck is a 2000 R/T

Thanks
Ben

[Jarheadoo7]

thats nuts! where did you get the battery that is in it?

[Swashbuckle]

Canadian Tire here in ontario, they won't replace it under warantee either because it still tests good.

[TazRango]

...

What does your gauge on the dash read? If it's above 14 volts, then the voltage regulator in the alternator has gone bad and is over charging the battery and you will need to replace the alternater.

[Swashbuckle]

I tested the battery at the terminals with the truck idleing it read 13.55V and at 1500 RPM it read 13.68 or something like that. The voltmeter in the dash when the truck was running always read a hair above 14V Ive never seen it any higher than that.

Originally Posted by Swashbuckle

I tested the battery at the terminals with the truck idleing it read 13.55V and at 1500 RPM it read 13.68 or something like that. The voltmeter in the dash when the truck was running always read a hair above 14V Ive never seen it any higher than that.

Then it's defintely not the alt then!

[txlen]

nope..is the sensor under the batt on the bottom of the tray still there???

[Swashbuckle]

The sensor is still there but was thinking it may be the culprit, is there anyway to test it out? They are asking $70 for them at the dealership!!!

[txlen]

only way i know is to look at the DRB and see what info it's getting... is it touching the battery???

[Swashbuckle]

I dont' know about that. I'm going to try swapping out my pcm to see if the problem goes away, just sucks because I dont want my MOPAR PCM to be messed up.

[txlen]

if yer sensor doesn't touch the batt it will screw up the charging that the pcm sees.....

[Swashbuckle]

well I swapped out the Mopar PCM and put the factory one back in, now I have no codes and the battery is no longer leaking.

I guess my next question is can anyone fix the regulator in the PCM or is it garbage?

CRAP.

[txlen]

Originally Posted by Swashbuckle

well I swapped out the Mopar PCM and put the factory one back in, now I have no codes and the battery is no longer leaking.

I guess my next question is can anyone fix the regulator in the PCM or is it garbage?

CRAP.

it's garbage !!

[Swashbuckle]

FRIG, even after I switched out the PCM I'am still having this problem. Is it possible for an alternator to test good on a bench test but still put out too much voltage? Another strange thing is that I have not recieved this engine code since I put the stock PCM back in but the battery still leaks.

I'm going crazy!!